MHB How does log2 (x+1)+3 equal 8(x+1)?

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The equation log2(x+1) + 3 does not equal 8(x+1); it is likely a typo. To clarify, taking the base 2 logarithm of 8(x + 1) yields log2(8) + log2(x + 1). Using the logarithm product rule, log2(8) simplifies to 3 since 2^3 equals 8. Therefore, log2(8(x + 1)) equals log2(x + 1) + 3, confirming the relationship. This demonstrates the correct interpretation of the logarithmic expression.
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Hey! Could someone explain how log2 (x+1)+3 equals 8(x+1)? Thank you!
 
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It doesn't, but I think it's a typo. I'll go on this assumption.

First look at $8(x + 1)$. Take its base 2 logarithm:

$$\log_2{(8(x + 1))}$$

Now remember the logarithm product rule:

$$\log{(xy)} = \log{(x)} + \log{(y)}$$

So apply this to what you have right now:

$$\log_2{(8(x + 1))} = \log_2{(8)} + \log_2{(x + 1)}$$

And since $2^3 = 8$, $\log_2{(8)} = 3$, and you can conclude:

$$\log_2{(8(x + 1))} = \log_2{(x + 1)} + 3$$
 
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